the tank is cobers, it just has the regaler plastic hoods with the lights, but on the one side i popped out the pre cut hole for the heater, i usually keep that hole covered, but the night before i was rearranging the tank a lil, and flipped over the background, i have places for them to hid, and as soon as the snow melts here, im going to the creek to get some stones for more hiding places. and with the cycling , when i had 1 wolf fish, i always keep the feeders in the same tank with him, so not only did i have just 1 wolf fish, there would also be 20-30 feeders with him.